Organic light emitting device, method for producing thereof and array of organic light emitting devices
View Patent ↗The present invention is directed to an organic light emitting device (OLED) including a first electrode, a second electrode, at least one layer of organic material arranged between the first electrode and the second electrode, and a dielectric capping layer arranged on the second electrode opposite to the first electrode, wherein the capping layer comprises an outer surface, opposite to the second electrode, for emission of light generated in the at least one layer of organic material. The capping layer has the effect that a reflectance of external light is reduced whereas outcoupling of the light generated in the at least one layer of organic material through the capping layer is increased.
1. An organic light-emitting device comprising:
a first electrode;
a second electrode;
at least one layer of organic material, arranged between the first electrode and the second electrode; and
a dielectric capping layer on the second electrode, the dielectric capping layer comprising a plurality of capping sublayers each with a different refractive index, wherein the refractive indexes of the capping sublayers increase or decrease monotonically with respect to a distance of each individual capping sublayer from the first electrode, and wherein the dielectric capping layer comprises PbSe, PbS, ZnSe, ZnS, or PbTe.
2. The organic light emitting device according to claim 1 , wherein the capping layer comprises an anomalous dispersive material.
3. The organic light emitting device according to claim 1 , wherein the first electrode comprises indium tin oxide.
4. The organic light emitting device according to claim 1 , wherein the second electrode comprises a LiF-layer, an Al-layer, a Li 2 O-layer, a CsF-layer, a Li-benzoate layer, a Li-acetonate layer, a calcium layer, a magnesium layer, a titanium layer, or a silver layer.
5. The organic light emitting device according to claim 1 , wherein the dielectric capping layer has a first thickness in the range of 35 nm to 45 nm, and wherein the organic light emitting device is structured to emit a maximum of luminance of light having a first wavelength between 400 nanometers (nm) to 700 nm and to reflect a minimum of light having a second wavelength incident on the organic light emitting device at the first thickness of the dielectric capping layer.